Dwarf wedgemussel habitat study on the upper Delaware river

This project analyzes the effect of flow regime changes in the Upper Delaware River on dwarf wedgemussel (DWM, Alasmidonta heterodon) habitat and develops strategies to avoid such impacts.  Results should aid in the protection and recovery of the dwarf wedgemussel, a federally endangered species.  The physical habitat conditions in 85 river miles are described using digital aerial photography and ground-based surveys.  MesoHABSIM and River2D habitat models are applied to identify the locations of potential suitable areas for the DWM.  Habitat suitability criteria are based on observations of velocity, depth, temperature, substrate and cover at existing DWM locations.  The multivariate habitat suitability criteria have been developed at two spatial scales (micro and meso) including temporal and spatial variability of complex hydraulics simulated by the model.  The habitat time series analysis serves to evaluate simulated flow-release scenarios and to compare the number of stress days occurring for the mussels under each of them.  The project will provide stake holders with a scientific basis for future flow and habitat management in the river.  The model can be used for habitat modeling of other species in the Delaware River.